SPARTA (7 Jul 2014)
# advect particles via VSS collisional flow on a uniform grid
# particles reflect off global box boundaries

variable            x index 10
variable            y index 10
variable            z index 10

variable            lx equal $x*1.0e-5
variable            lx equal 40*1.0e-5
variable            ly equal $y*1.0e-5
variable            ly equal 50*1.0e-5
variable            lz equal $z*1.0e-5
variable            lz equal 50*1.0e-5

variable            n equal 10*$x*$y*$z
variable            n equal 10*40*$y*$z
variable            n equal 10*40*50*$z
variable            n equal 10*40*50*50

seed	    	    12345
dimension   	    3
global              gridcut 1.0e-5

boundary	    rr rr rr

create_box  	    0 ${lx} 0 ${ly} 0 ${lz}
create_box  	    0 0.0004 0 ${ly} 0 ${lz}
create_box  	    0 0.0004 0 0.0005 0 ${lz}
create_box  	    0 0.0004 0 0.0005 0 0.0005
Created orthogonal box = (0 0 0) to (0.0004 0.0005 0.0005)
create_grid 	    $x $y $z
create_grid 	    40 $y $z
create_grid 	    40 50 $z
create_grid 	    40 50 50
Created 100000 child grid cells
  parent cells = 1
  CPU time = 0.00683308 secs
  create/ghost percent = 78.3531 21.6469

balance_grid        rcb part
Balance grid migrated 87500 cells
  CPU time = 0.0461371 secs
  reassign/sort/migrate/ghost percent = 14.3355 0.897614 24.4816 60.2854

species		    ar.species Ar
mixture		    air Ar vstream 0.0 0.0 0.0 temp 273.15

global              nrho 7.07043E22
global              fnum 7.07043E6

collide		    vss air ar.vss

create_particles    air n $n
create_particles    air n 1000000
Created 1000000 particles
  CPU time = 0.026412 secs

stats		    10
compute             temp temp
stats_style	    step cpu np nattempt ncoll c_temp

# first equilibrate with large timestep to unsort particles
# then benchmark with normal timestep

timestep 	    7.00E-8
run                 30
Memory usage per proc in Mbytes:
  particles (ave,min,max) = 13.3896 13.3896 13.3896
  grid      (ave,min,max) = 3.58589 3.58589 3.58589
  surf      (ave,min,max) = 0 0 0
  total     (ave,min,max) = 16.9755 16.9755 16.9755
Step CPU Np Natt Ncoll temp 
       0            0  1000000        0        0    273.35007 
      10   0.68893886  1000000   963967   705287    273.35007 
      20    1.3875668  1000000   990418   706678    273.35007 
      30      2.10111  1000000  1004087   706894    273.35007 
Loop time of 2.10115 on 8 procs for 30 steps with 1000000 particles

Particle moves    = 30000000 (30M)
Cells touched     = 147248057 (147M)
Particle comms    = 2540926 (2.54M)
Boundary collides = 2589124 (2.59M)
Boundary exits    = 0 (0K)
SurfColl checks   = 0 (0K)
SurfColl occurs   = 0 (0K)
Collide attempts  = 29062694 (29.1M)
Collide occurs    = 21102377 (21.1M)
Particles stuck   = 0

Particle-moves/CPUsec/proc: 1.78474e+06
Particle-moves/step: 1e+06
Cell-touches/particle/step: 4.90827
Particle comm iterations/step: 3
Particle fraction communicated: 0.0846975
Particle fraction colliding with boundary: 0.0863041
Particle fraction exiting boundary: 0
Surface-checks/particle/step: 0
Surface-collisions/particle/step: 0
Collision-attempts/particle/step: 0.968756
Collisions/particle/step: 0.703413

Move  time (%) = 1.07344 (51.0882)
Coll  time (%) = 0.866595 (41.2439)
Sort  time (%) = 0.148608 (7.07273)
Comm  time (%) = 0.000314564 (0.014971)
Outpt time (%) = 0.0121294 (0.577275)
Other time (%) = 6.17206e-05 (0.00293747)

Particles: 125000 ave 125753 max 123933 min
Histogram: 1 0 0 1 2 0 1 0 1 2
Cells:      12500 ave 12500 max 12500 min
Histogram: 8 0 0 0 0 0 0 0 0 0
GhostCell: 3173.5 ave 3538 max 2809 min
Histogram: 4 0 0 0 0 0 0 0 0 4
EmptyCell: 1477.5 ave 1842 max 1113 min
Histogram: 4 0 0 0 0 0 0 0 0 4
timestep 	    7.00E-9
run 		    100
Memory usage per proc in Mbytes:
  particles (ave,min,max) = 13.3896 13.3896 13.3896
  grid      (ave,min,max) = 3.58589 3.58589 3.58589
  surf      (ave,min,max) = 0 0 0
  total     (ave,min,max) = 16.9755 16.9755 16.9755
Step CPU Np Natt Ncoll temp 
      30            0  1000000  1004087   706894    273.35007 
      40     0.203969  1000000    90297    70314    273.35007 
      50   0.43191695  1000000    91677    70371    273.35007 
      60   0.65936184  1000000    93121    70771    273.35007 
      70   0.88615584  1000000    94010    70611    273.35007 
      80    1.1075029  1000000    95004    70893    273.35007 
      90    1.3285358  1000000    95293    70418    273.35007 
     100    1.5487499  1000000    96136    70518    273.35007 
     110    1.7516379  1000000    96340    70729    273.35007 
     120    1.9540348  1000000    96815    70512    273.35007 
     130    2.1553578  1000000    97353    70837    273.35007 
Loop time of 2.15539 on 8 procs for 100 steps with 1000000 particles

Particle moves    = 100000000 (100M)
Cells touched     = 139104236 (139M)
Particle comms    = 862119 (0.862M)
Boundary collides = 866994 (0.867M)
Boundary exits    = 0 (0K)
SurfColl checks   = 0 (0K)
SurfColl occurs   = 0 (0K)
Collide attempts  = 9370631 (9.37M)
Collide occurs    = 7015592 (7.02M)
Particles stuck   = 0

Particle-moves/CPUsec/proc: 5.79941e+06
Particle-moves/step: 1e+06
Cell-touches/particle/step: 1.39104
Particle comm iterations/step: 1
Particle fraction communicated: 0.00862119
Particle fraction colliding with boundary: 0.00866994
Particle fraction exiting boundary: 0
Surface-checks/particle/step: 0
Surface-collisions/particle/step: 0
Collision-attempts/particle/step: 0.0937063
Collisions/particle/step: 0.0701559

Move  time (%) = 1.01097 (46.9044)
Coll  time (%) = 0.555282 (25.7625)
Sort  time (%) = 0.50817 (23.5767)
Comm  time (%) = 0.0366588 (1.7008)
Outpt time (%) = 0.0441364 (2.04772)
Other time (%) = 0.000172347 (0.00799608)

Particles: 125000 ave 125623 max 124391 min
Histogram: 1 1 1 1 1 0 0 0 1 2
Cells:      12500 ave 12500 max 12500 min
Histogram: 8 0 0 0 0 0 0 0 0 0
GhostCell: 3173.5 ave 3538 max 2809 min
Histogram: 4 0 0 0 0 0 0 0 0 4
EmptyCell: 1477.5 ave 1842 max 1113 min
Histogram: 4 0 0 0 0 0 0 0 0 4

